MnO2/graphene composite electrodes for supercapacitors: the effect of graphene intercalation on capacitance

MnO2/graphene composites were prepared for the electrode material of supercapacitors. MnO2 was synthesized on a gold plate by the electrodeposition method. Graphene prepared by thermal CVD was transferred onto the MnO2 layer. These processes were repeated to make multilayer structures. The optimal performance of the MnO2/graphene composite was examined as a function of the number of graphene layers in MnO2. The morphology of MnO2 on graphene was confirmed by SEM and TEM, and the capacitance of the electrode was investigated by cyclic voltammetry and galvanostatic charge/discharge test. The graphene layer provides the electro-conductivity of MnO2, and then leads to enhancement of the capacitance of MnO2.